Mobile devices, such as personal digital assistants (PDAs), cellular telephones and smartphones, for example, often provide a user with the ability to carry out voice conversations with other parties. These mobile devices provide a user with a voice conversation experience much like that of traditional, land line telephones. However, the fact that mobile device are in fact mobile or portable gives rise to certain new scenarios during which a voice conversation can be effectuated. For example, while driving a car, a user of a mobile device may receive a telephone call on their mobile device. Another example is that a user may bring their mobile device to their place of employment and receive personal telephone calls on their mobile device while at work.
Mobile devices are becoming increasingly feature rich as manufacturers try to attract the attention of increasingly discerning consumers. One such feature which is becoming more popular is the ability for a mobile device to enable voice conversations to be carried out using a speakerphone. In a voice conversation carried out using a speakerphone, the user of the mobile device does not need to hold the mobile device to their ear. The user's voice is captured by a microphone and the voice of the person at the other end of the conversation is relayed to the user using a speaker. Mobile devices featuring speakerphone ability allow the user to manually switch between traditional or handset mode (holding the mobile device up to one's ear, as with traditional land line telephones) and speakerphone mode. The switch between the two modes (handset mode and speakerphone mode) is traditionally carried out by, for example, the user's selection of a menu item on the screen of the mobile device or the user's activation of a predefined button or key sequence.
A user is therefore required to manually interact with the mobile device in order to switch between handset mode and speakerphone mode. This manual interaction requires a mobile device's user to look at the mobile device and may take a few seconds to execute.
A variety of solutions to this problem have been proposed.
U.S. Pat. No. 5,224,151 to Donald J Bowen et al. is entitled “Automatic Handset-Speakerphone Switching Arrangement for Portable Communication Device” (the '151 patent). In the '151 patent, a portable communication device (mobile device) is disclosed which automatically transitions between a handset mode and a speakerphone mode based on a continuous distance measurement between the handset audio output device and the user's ear. This distance measurement is determined by an infrared range detection unit or other distance determination methods such as acoustic echo return systems built into the handset. However, the solution disclosed in the '151 patent requires that a distance measuring system be added to a mobile device. The '151 patent is predicated on a mobile device sending an output signal and waiting to receive that output signal back as an input signal in order to measure distance. The '151 patent discloses a system which may not work if the user of the mobile device were to place the mobile device in their pocket or in a holder for example, as the distance measurement could become inaccurate.
U.S. Pat. No. 6,411,828B1 to Lands et al. is entitled “Communications Devices and Methods that Operate According to Communications Device Orientations Determined by Reference to Gravitational Sensors” (the '828 patent). The '828 patent discloses that a mode of operation of a communications device transitions from the selected speakerphone mode to handset mode of operation based on movement of the communications device from a first orientation (e.g. Vertical) to a second orientation (e.g. Horizontal). The system disclosed requires that a gravitational sensor be added to a mobile device, increasing both the complexity and cost of the mobile device. Further, the system may not work as desired if the user would like to use speakerphone mode when their mobile device is not lying flat, when the mobile device is in a holder for example.
U.S. Pat. No. 5,712,911 to Ju-Won Her is entitled “Method and System for Automatically Activating and Deactivating Speakerphone” (the '911 patent). In the '911 patent is disclosed a system where a proximity sensor is used to determine if a phone call should be commenced in speakerphone mode. The embodiment disclosed includes commercially available infrared sensors to sense the presence or absence of the subscriber in the predetermined proximity zone. The '911 patent requires the use of an external proximity detection system attached to a user and is not geared towards a mobile device.
There is a need for an improved mobile device which allows a user to automatically switch between handset mode and speakerphone mode which overcomes some of the limitations presented by prior attempts to solve this problem.